Endoscope



E. E. BAKER Jan. 29, 1957 ENDOSCOPE Filed July 2, 1953 INI/ENTOR.V ELVI'N E. BAKER Y 4A ATTORNEYS l United States Patent O ENDOSCOPE Elvin E. Baker, Havertown, Pa., assgnor to George P.

Pilling & Son Company, Philadelphia, Pa., a corporation of Pennsylvania Application July 2, 1953, Serial No. 365,581

3 Claims. (Cl. 12S-6) This invention relates to the construction of endoscopes, using this term ina broad sense to include various elongated instruments such as bronchoscopes and gastroscopes or the like as may be used in the medical profession and similar instruments as may be used in other types of applications.

In the construction of endoscopes it has been the conventional practice to provide electrical conductors extending through the endoscope from the eye piece or proximal end to the distal end in order to energize illuminating means mounted at the distal end and also, in some instances, to provide power to cautery elements, electromotive units and other types ot' electrically operated apparatus at the distal end.

Heretofore, it has been the general practice to provide one or more conductors in the form of-wire to carry the elec-tric current to the apparatus at the distal end of the endoscope. When it is considered that the endoscopes generally employed, for example, in the medical profession, have a very large ratio of length to diameter and their external diameters may, in some cases, be less than 0.2 inch, it will be evident that, particularly when it is necessary to leave the central region of the tubes forming the endoscope open to provide a passage for the transmission of light therethrough and the positioning of a lens system therein, it is diflicult to install independent conductors and that these conductors, due to the ex tremely tine diameters to which they are limited, are subject to failure from conditions of overcurrent from corrosion and from mechanical causes.

lt is an object of the present invention to provide an endoscope constructed from a pair of tubes arranged one within the other which are insulated from one another and which form not only the barrel of the endoscope within which there may be conveniently supported a lens system but which also provide the two conductors necessary to transmit a flow of electric current from the proximal end of the endoscope to the distal end of the endoscope. Consruction of this type eliminates the need for the provision of one or more separate conductors and adapts itself to the connection of a source of power thereto at the proximal end and to the inclusion therein of a lamp or other electric current consuming means at the distal end.

The foregoing and other objects of the invention relating particularly to details of construction will become apparent from the following description when read in conjunction with the accompanying drawing in which:

Figure l is a radial section through the proximal or eye piece end of an endoscope constructed in accordance with the present invention; and

Figure 2 is a similar section of the distal end thereof.

Figures l and 2 show the proximal and distal ends of an endoscope provided with a long outer tube 2. Located within the -tube 2 is an inner tube 4. .The tubes 2 and 4 are formed of a suitable metal having the necessary strength and rigidity as required in endoscopes and having suitable electrical conductivity to provide a pair of conductors for the flow of electric current therethrough: as will be hereinafter described. The inner tube i is in-4 sulated from the outer tube 2 by a coating 6 of insulat-j ing lacquer, though under some circumstances an actual separate insulating tube may be provided. The Outer: tube 2 is secured by braising or soldering in one end of a sleeve 8 which receives a tube 10 insulated from it by an insulating coating 12 or an insulating tube in thesame position. An insulating member 14 is internally' threaded for association with external threads provided. on the sleeve 8 and is, in turn, externally threaded for' assembly with a conducting member 1.6. An externally and internally ilanged insulating member 13 and a metallic spacer 20 are clamped together and against the member i6 by a nut 22 threaded upon the sleeve 3. A set screw 23 or other suitable means may be provided to lock the nut 22 in position on the threaded sleeve 8.

A tubular lateral extension 24 of suitably conductive metal is threaded into the spacer 20 and is provided with a pin 26 for providing engagement with the bayonet slot of a conventional electrical lead assembly which is not shown. A pin 28 extends axially through the tube 24 and is insulated therefrom by passage through insulating plugs 30 and 32. The inner end of pin 28 is secured in 'the side wall of a metallic cup 34 which rests within the internally flanged insulating member 1S and provides a seal for a metallic spring 36 which serves to urge against the member 16 a flanged cylindrical metallic member 3S. The ange 40 of the tube 10 is clamped against the member 16 by an annular nut 42 threaded into the member 16. Threaded on the proximal end of the tube 10 is an aperture-forming cup 44. Beyond this there is carried the protective glass disc 43 secured in the support 46 which is threaded into the proximal end of the member 16. An eye piece member providing a light shield is provided at Sti externally threaded upon the member 16.

Referring now to the distal end of the instrument, there is provided what is in elect an extension of the inner tube 4 in the form of a separate metallic tube 52. this being coupled to the tube flby a coupling sleeve 54. Both the tube 52 and the sleeve 54 are formed of a suitably conductive metal.

vide for the entrance of light waves to an objective lens or other suitable reflecting or refracting means 74.

The tubes 2 and 52 are spaced by means of an insulating coating 53 which may, similarly to the insulating coating 6, be under some circumstances a separate insu lating tube. The outer ends of the tubes 2 and 52 beyond the aperture 56 are provided with an aperture 58 which is covered by a transparent plastic window 60 behind which there is located an illuminating lamp 62. A rounded end plug 64 is threaded into the distal end of the outer tube 2 and is provided with a socket for the reception of a spring 66 which presses a metallic button 68 against the central Contact 70 at the base of the lamp 62. The other Contact of the lamp is provided by its peripheral tlange 72 which is pressed by the action of the spring 66 against the end of the tube :32. Y

The electrical circuit of the lamp may be traced from pin 26 through tube 24, spacer 20, nut 22, sleeve 8, outer tube 2, plug 64, spring 66, button 68 to contact 7i) which fis electrically joined in the lamp to one end of the lamp filament. The other end of the lamp tilament is electrically joined to ilange 72 which completes 4the circuit through tube 52, coupling 54, inner tube d, tube it), member 16, member 38, spring 36, cup 3d and pin 28. All of these elements are metallic and, consequently, a circuit is provided between pins 26 and 28 which are respectively connected to the terminals of a liexible electrical lead in any conventional manner. it will be evi- The outer tube 2 and the tube 52 are provided with aligned apertures at 56 to prodent that this structure provides an extremely suitable and compact yet 'highly reliable means for conducting the oW of electric current from terminals at the eye piece of the endoscope to a lamp positioned within the distal end of the endoscope tubes,

In addition to providing a highly reliable electrical circuit having substantially greater electrical capacity than could ordinarily be achieved by the use of a pair of conductive wires. extending the length of the endoscope this construction permits the unobstructed inclusion within the inner tube of optical eiements titi, 82 and 4, which, cooperating with the objective 74', transmit an image to the eye of a viewer located adjacent to the glass disc 4S in the eye piece. It is believed that the advantages of being able to position optical elements such as titl and S2 within the tubes and to locate these elements by means of supporting tubes such as S6 and 88 without the necessity of making provision for the passage of individual conductors are self evident. Such a lens system is disclosed in detail in the patent application of Robert H. Peckham, Serial No. 367,855, filed July 14, 1953.

While the apparatus has been disclosed in the form of an endoscope having illuminating means and light receiving means mounted in the distal end thereof, it will be evident that various types of endoscopes in which there is involved the necessity of retaining minimum dimensions Iand an unobstructed central passage along with perfectly smooth external surfaces may be desirably constructed in accordance with this invention to provide for a supply of electric current to electrical apparatus at the distal end thereof.

it should be noted that the construction of an endoscope incorporating the principles disclosed herein is not iimited to two tubes. For example, an additional tube may be included to provide for aspirating or other possibie functions. it is additionally noted that the tubes fre not necessarily concentrically arranged. In fact, :n some occasions eccentricity may be desirable such as, for example, where additional elements extending between the proximal and distal ends of the tubes are desir-ably provided. Under these conditions the two tubes might desirably be arranged in non-concentric relation in order to provide spacing for the passage of such elements.

What is claimed is:

l. in an endoscope a pair of conductors in the form ci a pair of tubes one within the other extending substantially the length of the instrument, mounting means for eiectrically operated means positioned lat the distal ends of said conductor tubes, said mounting means mcluding a ilange adapted to malte contact with the distal Cil end of the inner of said conductor tubes and a central contact member on the distall side ofA the flange, means for closing off the distal end of the outer of said conductor tubes, yielding means acting between said closing means and said central contact member for urging the said frange into Contact with the distal end of the inner oi: said conductor tubesandV for making contact between said central contact member and said closing means, and means providing for the connection of a source of electricity. to the proximal' ends of the conductors.

2. in an endoscope a pair of conductors in 'the form of a pair of tubes one within the otherr extending substantially thelength of theinstrumengmeans `connected to the distal end of the inner of said conductor tubes internaliy of the outer of said conductortubes for mounting optical apparatus and electrically operated means, means connected to the outer of said tubes for positioning said mounting meansand said optical and electrically operated means, said mounting means being removable from. the distal end of the apparatus upon removal of said positioning and mounting means without disassern bly of the remainder of the apparatus, means providing electrical connections between said pair of tubes and said electrically operated means, and means providing for thc connection of a source of electricity to the proximal ends ot" the conductors.

3. in an endoscope a pair of conductors in the form of a pair of tubes one within the other extending subk santially the length of the instrument, means connected to the distal end of the inner of said conductorV tubes internally of the outer of said conductor tubes for mounting optical apparatus and electrically operated means, means connected to the outer of said tubes for positioning said mounting means and said optical land electrically operated means,` said mounting. means being removable from the distal end of the apparatus upon removal of said positioning and mounting means without disassem bly of the remainder oi the apparatus, means including said last two mentioned means providing electrical connections between said pair of tubes and said electrically operated means, and means providing for the connection oi a source of electricity to the proximal ends of the conductors.

ReferencesV Citedin the tile of this patent UNITEDv STATES PATENTS 598,787 Kelling Feb. 8, i898 2,516,882 Kalom Aug. l, 1950 FOREIGN PATENTS 555,600 France Mar. 26, 1923 

